How to display a Entity Reference link in a separate window/tab or in modal window?

(D7 question): We have a section where users can enter a reference to videos, and the options include either videos already on this site or on other sites such as youtube. We want to avoid the links opening in the same page, which is easily accomplished with standard configuration options for the “other sites” URL field. For videos already in this site, we’re allowing entry via an autocomplete Entity Reference field. The resulting link does not have an option to open it in a separate window. Is there a way around that, short linking to custom JS for the site? Maybe another module to modify options for file entities?

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